Aimed at the problems that aero-engine combustors need urgently to widen stability and prevent flameout under conditions of fast fuel reduction to verify the effect of plasma-assisted combustion (PAC) technology in widening the dynamic limit and other aspects, a swirl experimental platform is established with single dome under conditions of fast fuel reduction, and the dynamic characteristics study is conducted based on gliding arc plasma. Through collecting OH* chemical luminescence signals in the combustion process of fast fuel reduction, the combustion chamber flameout evolution process is analyzed, and then the influence of gliding arc plasma excitation on flameout characteristics is studied at different fuel reduction rates and flows in comparison. The results show that the lean blowout limit under dynamic fuel reduction is significantly smaller than that under quasi-steady conditions, and the lean blowout limit becomes narrower with the increase of dynamic fuel reduction and inlet airflow. After the application of PAC, the assisted combustion effect is significant, and the lean blowout fuel-air ratio of the fast fuel reduction condition is significantly reduced, especially under larger fuel reduction rate and inlet airflow can still maintain stable combustion. The limit widening is the largest at inlet airflow of 15 m3/h and fuel reduction rate of 009/s, widening from 0064 to 0052, and the widening degree reaches 23%.